Test: Crop Improvement - Class 9 MCQ

Green manure is a term used to describe crops or plants which are grown for the purpose of manuring the soil. Green manure crops are grown, cut and ploughed in the soil to enhance the soil fertility. Green manuring is an eco-friendly method of manuring the soil. Examples of green manure crops include sunhemp, dhaincha etc.

Pusa Lerma was developed from the wheat category named  Lerma Rojo using  mutation breeding owing to the objection of farmers to use the wheat supplied having low market value by Mexico to India.

The Catla fish is an economically very important South Asian freshwater fish. It is in the carp family Cyprinidae. It is known by many different names such as Katla, Katol, Indian Major carp, Chepti, Baudhekra, Bacha, Karakatla and Tambra. The fish is mainly found in the rives and lakes in northern India, Bangladesh, Nepal, Pakistan and Myanmar.

The amount of humus found in soil also increases with higher rate of decomposition, which is beneficial for the growth of crop succeeding the green manure crop.

Application of nitrogenous manure to a plant causes vigorous vegetative growth.

Some plants like sun hemp or guar are grown in the field prior to the sowing of the crop seeds. These are then mulched by ploughing them into the soil. These green plants gradually decompose and turn into green manure which helps in enriching the soil in nitrogen and phosphorus.

Herbicide, an agent, usually chemical, for killing or inhibiting the growth of unwanted plants, such as residential or agricultural weeds and invasive species. A great advantage of chemical herbicides over mechanical weed control is the ease of application, which often saves on the cost of labour. Most herbicides are considered nontoxic to animals and humans, but they can cause substantial mortality of nontarget plants and the insects that depend on them, especially when applied aerially.

GM crops are made through a process known as genetic engineering. Genes of commercial interest are transferred from one organism to another. Two primary methods currently exist for introducing transgenes into plant genomes. The first involves a device called a 'gene gun'.

Because rats do not cause harm to the plants whereas bacteria,fungi and viruses cause diseases in plants..

The pigeon pea is a perennial legume from the family Fabaceae. Since its domestication in the Indian subcontinent at least 3,500 years ago, its seeds have become a common food in Asia, Africa, and Latin America.